# US 11,440,981 B2 · Aqueous polymerization of fluorinated monomer using polymerization agent comprising fluoropolyether acid or salt and short chain fluorosurfactant

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,440,981 B2
- Document ID: US11440981B2
- Status: Granted
- Kind: B2
- Application number: 13/965,317
- Filed: 2013-08-13
- Published: 2013-12-12
- Granted: 2022-09-13
- Earliest claimed: 2006-11-09
- Assignees: The Chemours Company Fc, LLC
- Applicants: The Chemours Company Fc LLC
- Inventors: Paul Douglas Brothers; Subhash Vishnu Gangal
- Web page: https://patentgrep.com/patent/US11440981B2

## CPC

- C08F 14/26: Tetrafluoroethene
- C08F 14/18: Monomers containing fluorine
- C08F 214/262: {with fluorinated vinyl ethers}
- C08K 3/20: Oxides; Hydroxides {(graphene oxides C08K3/042)}
- C08L 27/18: Homopolymers or copolymers or tetrafluoroethene
- C08L 2201/54: Aqueous solutions or dispersions
- C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09)
- C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06)

## Abstract

A process comprising polymerizing at least one fluorinated monomer in an aqueous medium containing initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer, the polymerization agent comprising: fluoropolyether acid or salt thereof having a number average molecular weight of at least about 800 g/mol; and fluorosurfactant having the formula: [R1—On-L-A−]Y+ wherein: R1 is a linear or branched partially or fully fluorinated aliphatic group which may contain ether linkages; n is 0 or 1; L is a linear or branched alkylene group which may be nonfluorinated, partially fluorinated or fully fluorinated and which may contain ether linkages; A− is an anionic group selected from the group consisting of carboxylate, sulfonate, sulfonamide anion, and phosphonate; and Y+ is hydrogen, ammonium or alkali metal cation; with the proviso that the chain length of R1—On-L- is not greater than 6 atoms.

## Claims

### Claim 1

A process comprising polymerizing at least one fluorinated monomer in an aqueous medium containing initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer, said polymerization agent comprising:
fluoropolyether acid or salt thereof having a number average molecular weight of at least about 800 g/mol; and
fluorosurfactant having the formula:
[R1—On-L-A−]Y+
wherein:
R1 is a linear or branched partially or fully fluorinated aliphatic group which may contain ether linkages;
n is 1;
L is a linear or branched alkylene group which may be non-fluorinated, partially fluorinated or fully fluorinated and which may contain ether linkages;
A−is a carboxylate; and
Y+is hydrogen, ammonium or alkali metal cation;
with the proviso that the chain length of R1—On-L- is not greater than 6 atoms,
wherein said polymerization agent comprises a minor amount of said fluoropolyether acid or salt thereof and a major amount of said fluorosurfactant;
wherein said polymerizing produces less than about 3 wt % undispersed fluoropolymer based on the total weight of fluoropolymer produced; and
said process further comprising forming a mixture of a polymerization agent comprising a fluoropolyether acid or salt in acid form and a fluorosurfactant in acid form and dispersing said mixture in an aqueous medium.

### Claim 2 (depends on 1)

The process of claim 1 wherein said chain length of R1-0n-L- is 3 to 6 atoms.

### Claim 3 (depends on 1)

The process of claim 1 wherein said chain length of R1-0n-L- is 4 to 6 atoms.

### Claim 4 (depends on 1)

The process of claim 1 wherein said chain length of R1-0n-L- is 3 to 5 atoms.

### Claim 5 (depends on 1)

The process of claim 1 wherein said chain length of R1-0n-L- is 4 to 5 atoms.

### Claim 6 (depends on 1)

The process of claim 1 wherein:
R1 is a linear or branched partially or fully fluorinated alkyl group having 1 to 3 carbon atoms which may contain ether linkages; and
L is an alkylene group selected from —CX(R2)—, wherein R2 is fluorine or perfluoromethyl and X is hydrogen or fluorine, and —CZ1Z2CZ3Z4—, wherein Z1, Z2, Z3, and Z4 are independently selected from the group consisting of hydrogen and fluorine.

### Claim 7 (depends on 6)

The process of claim 6 wherein:
L is an alkylene group selected from the group consisting of —CF(CF3)—, —CF2—, —CF2CF2—, —CHFCF2—, and —F2CHF—.

### Claim 8 (depends on 1)

The process of claim 1 wherein R1 is a linear partially or fully fluorinated alkyl group having 2 to 3 carbon atoms.

### Claim 9 (depends on 1)

The process of claim 1 wherein R1 is fully fluorinated.

### Claim 10 (depends on 1)

The process of claim 1 wherein:
R1 is CF3CF2CF2—,
L is —CF(CF3)—; and
Y+is hydrogen or ammonium.

### Claim 11 (depends on 1)

The process of claim 1 wherein said aqueous medium contains less than about 300 ppm of perfluoroalkane carboxylic acid or salt fluorosurfactant having 8 or more carbon atoms based on the weight of water in said aqueous medium.

### Claim 12 (depends on 1)

The process of claim 1 wherein said fluoropolyether acid or salt thereof having a number average molecular weight of at least about 800 g/mol comprises acid groups selected from carboxylic acid, sulfonic acid, sulfonamide, phosphonic acid.

### Claim 13 (depends on 1)

The process of claim 1 wherein said fluoropolyether acid or salt thereof has a number average molecular weight of about 800 to about 3500 g/mol.

### Claim 14 (depends on 1)

The process of claim 1 wherein said fluoropolyether acid or salt thereof has a number average molecular weight of about 1000 to about 2500 g/mol.

### Claim 15 (depends on 1)

The process of claim 1 wherein said polymerization agent is present in said aqueous medium in an amount of about 5 ppm to about 3000 ppm based on the weight of water in said aqueous medium.

### Claim 16 (depends on 1)

The process of claim 1 wherein said aqueous dispersion of particles of fluoropolymer formed by said process has a fluoropolymer solids content of about 20 wt % to about 65 wt %.

### Claim 17 (depends on 1)

The process of claim 1 wherein said at least one fluorinated monomer is selected from the group consisting of tetrafluoroethylene (TFE), hexafluoropropylene (HFP), chlorotrifluoroethylene (CTFE), trifluoroethylene, hexafluoroisobutylene, perfluoroalkyl ethylenes, fluorovinyl ethers, vinyl fluoride (VF), vinylidene fluoride (VF2), perfluoro-2,2-dimethyl-1,3-dioxole (PDD), perfluoro-2-methylene-4-methyl-1,3-dioxolane (PMD), perfluoro(allyl vinyl ether) and perfluoro(butenyl vinyl ether).

### Claim 18 (depends on 1)

The process of claim 1 wherein said particles of fluoropolymer produced comprise PTFE or modified PTFE having a comonomer content of no greater than about 1 wt %.

### Claim 19 (depends on 1)

The process of claim 1 wherein said fluorosurfactant comprises at least about 55 wt % of said polymerization agent.

### Claim 20 (depends on 1)

The process of claim 1 wherein said fluorosurfactant comprises at least about 65 wt % of said polymerization agent.

### Claim 21 (depends on 1)

The process of claim 1 wherein said particles of fluoropolymer produced comprise a melt-processible copolymer comprising at least about 60-98 wt % tetrafluoroethylene units and about 2-40 wt % of at least one other monomer.

### Claim 22 (depends on 1)

The process of claim 1 wherein said aqueous medium is substantially free of perfluoropolyether oil.

### Claim 23 (depends on 1)

The process of claim 1 wherein said polymerization medium is substantially free of fluoropolymer seed at polymerization kick-off.

### Claim 24 (depends on 1)

The process of claim 1 wherein L contains at least one ether linkage.

### Claim 25

A process comprising polymerizing at least one fluorinated monomer in an aqueous medium containing initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer, said polymerization agent comprising:
fluoropolyether acid or salt thereof having a number average molecular weight of at least about 800 g/mol; and
fluorosurfactant having the formula:
[R1—On-L-A−]Y+
wherein:
R1 is a linear or branched partially or fully fluorinated aliphatic group which may contain ether linkages;
n is 1;
L is a linear or branched alkylene group which may be non-fluorinated, partially fluorinated or fully fluorinated and which contains at least one ether linkage;
A−is a carboxylate; and
Y+is hydrogen, ammonium or alkali metal cation;
with the proviso that the chain length of R1—On-L- is not greater than 6 atoms,
wherein said polymerization agent comprises a minor amount of said fluoropolyether acid or salt thereof and a major amount of said fluorosurfactant; and
wherein said polymerizing produces less than about 3 wt % undispersed fluoropolymer based on the total weight of fluoropolymer produced.

### Claim 26 (depends on 25)

The process of claim 25 wherein R1 is a linear partially or fully fluorinated alkyl group having 2 to 3 carbon atoms.

### Claim 27 (depends on 25)

The process of claim 25 wherein R1 is fully fluorinated.

### Claim 28 (depends on 25)

The process of claim 25 wherein said aqueous medium contains less than about 300 ppm of perfluoroalkane carboxylic acid or salt fluorosurfactant having 8 or more carbon atoms based on the weight of water in said aqueous medium.

### Claim 29 (depends on 25)

The process of claim 25 wherein said fluoropolyether acid or salt thereof having a number average molecular weight of at least about 800 g/mol comprises acid groups selected from carboxylic acid, sulfonic acid, sulfonamide, phosphonic acid.

### Claim 30 (depends on 25)

The process of claim 25 wherein said fluoropolyether acid or salt thereof has a number average molecular weight of about 800 to about 3500 g/mol.

### Claim 31 (depends on 25)

The process of claim 25 wherein said fluoropolyether acid or salt thereof has a number average molecular weight of about 1000 to about 2500 g/mol.

### Claim 32 (depends on 25)

The process of claim 25 wherein said polymerization agent is present in said aqueous medium in an amount of about 5 ppm to about 3000 ppm based on the weight of water in said aqueous medium.

### Claim 33 (depends on 25)

The process of claim 25 wherein said aqueous dispersion of particles of fluoropolymer formed by said process has a fluoropolymer solids content of about 20 wt % to about 65 wt %.

### Claim 34 (depends on 25)

The process of claim 25 wherein said at least one fluorinated monomer is selected from the group consisting of tetrafluoroethylene (TFE), hexafluoropropylene (HFP), chlorotrifluoroethylene (CTFE), trifluoroethylene, hexafluoroisobutylene, perfluoroalkyl ethylenes, fluorovinyl ethers, vinyl fluoride (VF), vinylidene fluoride (VF2), perfluoro-2,2-dimethyl-1,3-dioxole (PDD), perfluoro-2-methylene-4-methyl-1,3-dioxolane (PMD), perfluoro(allyl vinyl ether) and perfluoro(butenyl vinyl ether).

### Claim 35 (depends on 25)

The process of claim 25 wherein said particles of fluoropolymer produced comprise PTFE or modified PTFE having a comonomer content of no greater than about 1 wt %.

### Claim 36 (depends on 25)

The process of claim 25 wherein said fluorosurfactant comprises at least about 55 wt % of said polymerization agent.

### Claim 37 (depends on 25)

The process of claim 25 wherein said fluorosurfactant comprises at least about 65 wt % of said polymerization agent.

### Claim 38 (depends on 25)

The process of claim 25 wherein said particles of fluoropolymer produced comprise a melt-processible copolymer comprising at least about 60-98 wt % tetrafluoroethylene units and about 2-40 wt % of at least one other monomer.

### Claim 39 (depends on 25)

The process of claim 25 wherein said aqueous medium is substantially free of perfluoropolyether oil.

### Claim 40 (depends on 25)

The process of claim 25 wherein said polymerization medium is substantially free of fluoropolymer seed at polymerization kick-off.

### Claim 41 (depends on 25)

The process of claim 25 wherein said chain length of R1—On-L- is 4 to 5 atoms.